The Federal Election Commission, in the midst of what is shaping up to be the most expensive presidential campaign in history, cannot begin new investigations or file lawsuits because four spots on the six-member board are vacant.
The FEC also cannot certify matching funds for presidential candidates seeking public campaign money until the vacancies are filled.
The unfilled positions stem from a political stalemate over President Bush's nomination of Hans A. von Spakovsky to the commission. Mr. von Spakovsky, a former Georgia elections official and a lawyer in the Justice Department, served on the board last year as a recess appointment.
But Democratic Sens. Barack Obama of Illinois and Russ Feingold of Wisconsin have put holds on the appointment, prompting Senate Minority Leader Mitch McConnell to insist that Mr. von Spakovsky's vote be part of a slate with three other pending FEC nominations.
The deadlock has held up all four nominations and left the bipartisan board with two members, which is short of a quorum needed to conduct major business.
FEC officials said the matter hasn't stopped the commission from conducting its daily business. The commission's auditors, lawyers and investigators continue to review and process campaign-disclosure reports.
The board is scheduled to meet Jan. 24 to discuss advisory opinions and administrative matters.
Mr. Obama, who is seeking his party's presidential nomination, has raised concerns about what he called Mr. von Spakovsky's "active role" in a Georgia state law requiring voters to provide certain forms of official identification at the polls. He also questioned Mr. von Spakovsky's tenure as a lawyer with the Justice Department's Civil Rights Division.
But Mr. McConnell, Kentucky Republican, has defended Mr. von Spakovsky's record and said the FEC always has had three nominees each for Democrats and for Republicans.
"I think that's the right way to structure an agency like that, that could have a huge and adverse partisan impact on one party or the other," he said last month.
"The Democrats have their nominations, and we've picked ours," he said. "What we have here ... the Democrats trying to veto one of our nominees. That isn't going to happen. They're all four going to go together, or none of them will be approved."
Presidential candidates who have been certified for seeking public funding could have to wait until the deadlock is resolved.
Former Sen. John Edwards of North Carolina, who also is seeking the Democratic nomination, has sought matching funds from the FEC. Sen. John McCain of Arizona, the front-runner among Republicans seeking the party's presidential nomination, also has filed paperwork for matching funds.
"We have the necessary resources to wage an aggressive campaign with the resources we currently have on hand," said Edwards campaign spokesman Eric Schultz. "We fully expect the FEC to meet their obligations under the public-financing system."